The present disclosure relates generally to systems and methods for improving the efficiency of a display panel, and more specifically, to improving the efficiency of a boost converter in the display panel while operating under light-load conditions.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
A backlight driver circuit in a light-emitting diode (LED) display may use a boost converter to provide a range of direct current (DC) voltages to a string of light-emitting diodes (LEDs) in the LED display. Generally, the string of LEDs provides various amounts of white light to the screen of the LED display such that the range of DC voltages corresponds to a range of brightness levels or white light provided to the screen. To control the range of voltages provided to the string of LEDs, the backlight driver circuit may use the boost converter to adjust (e.g., increase) an input voltage provided by a voltage supply and couple the adjusted voltage to the string of LEDs. Generally, the boost converter adjusts the voltage of the voltage supply by turning a switch (e.g., metal-oxide-semiconductor field-effect transistor) on and off such that an inductor coupled in series with the voltage supply and the string of LEDs may maintain a voltage, which may increase a total voltage available to the string of LEDs.
In conventional backlight driver circuits, the boost converter is configured to switch a metal-oxide-semiconductor field-effect transistor (MOSFET) using a fixed gate drive voltage to minimize a power loss in the MOSFET. That is, the backlight driver circuit may provide a fixed gate drive voltage to the gate of the MOSFET to switch the MOSFET off and on such that an on-resistance Rds(on) between the drain and the source in the MOSFET is minimized, thereby decreasing conduction losses of the MOSFET due to the on-resistance Rds(on). However, during light-load conditions, a large portion of the power loss of the MOSFET may no longer be attributed to the power lost via the on-resistance Rds(on). Instead, during light-load conditions, a large portion of the power loss of the MOSFET may be attributed to driving the gate of the MOSFET when the MOSFET switches. As such, by using the fixed gated drive voltage for all load conditions (i.e., including light-load conditions), the boost converter may be less efficient due to the power loss via the gate of the MOSFET.